Manage your subscription

Toddlers cannier than scientists thought

By Debora MacKenzie

One-year-olds are supposed to learn by copying adults – but now it seems they only copy us if it what we are doing makes sense to them.

The question arose from experiments in the 1980s by Andrew Meltzoff of the University of Washington in Seattle. An adult turned on a light by head-butting a large push-button light switch as a group of fourteen-month-olds watched. Later, two-thirds of the toddlers copied her, head-butting the switch to turn the light on instead of using their hands. No toddler did this unless they had seen an adult do it.

From this, Meltzoff inferred that, unlike primates, human children really do learn by “aping” adult behaviour. Another primate would grasp the goal and use an action it had already learned – such as pushing buttons by hand – to achieve it.

But György Gergely of the Institute for Psychology at the Hungarian Institute of Sciences in Budapest thought this did not square with other research which suggested that toddlers can figure out whether the means an adult used to achieve a goal made sense, and should be copied.

Advertisement

So he repeated the experiment – but in half the cases the demonstrator wrapped a shawl around herself and held it with both hands. In the other half, her hands were visible on the table.

Complex behaviours

Gergely found that two-thirds of the toddlers copied her – but only if her hands were clearly unoccupied. Only a fifth of them were to be seen head-butting the switch later if they had watched the demonstrator do it while her hands were clearly occupied.

The toddlers reasoned, Gergely surmises, that if the adult head-butted the switch while her hands were free, then that must be the best way to do it. But if her hands were occupied, then surely that must have been why she used her head – not an action toddlers with a free hand need emulate.

He concludes that toddlers copy us, but based on an “evaluation of the rationality of the means in relation to the constraints of the situation”. Whether this applies to the more complex behaviours they need to learn as teenagers remains to be tested.